Method and device for supporting a conveyed tank
against roll and pitch

ABSTRACT

1. AN AUXILIARY DEVICE FOR SUPPORTING A TANK AGAINST ROLL AND PITCH AND ASSOCIATED WITH A SYSTEM OF MAIN MOVABLE AND SUBSTANTIALLY VERTICAL SUSPENSION SUPPORTS, SAID DEVICE COMPRISING AT LEAST ONE SET OF STATIONARY BEARING MEMBERS SUBSTANTIALLY ADJACENT TO ONE ANOTHER AND DISTRIBUTED ALONG THE PERIPHERY OF SAID TANK AT LEAST APPROXIMATELY IN ONE AND THE SAME RELATIVE HORIZONTAL PLANE, EACH BEARING MEMBER COMPRISING A SUBSTANTIALLY TRIANGULAR BRACKET SUPPORT COMPRISING IN PARTICULAR TWO OVERHANGING RODS, A STATIONARY EXTERNAL STRUCTURE SPACED FROM SAID TANK, (RESPECTIVELY AT TWO, AT LEAST HORIZONTALLY SPACED POINTS OF THE TANK LOCATED RESPECTIVELY ON EITHER SIDE OF THE NORMAL RELATIVE VERTICAL PLANE PASSING THROUGH SAID MEMBER), ONE OF THE ENDS OF SAID RODS BEING CONNECTED TO SAID STRUCTURE, SAID RODS PROJECTING RESPECTIVELY FROM TWO AT LEAST HORIZONTALLY SPACED POINTS OF SAID STRUCTURE LOCATED RESPECTIVELY ON EITHER SIDE OF THE NORMAL RELA-   TIVE VERTICAL PLANE PASSING THROUGH SAID MEMBER AND SAID RODS CONVERGING TOWARDS SAID PLANE, A GUIDING ELEMENT INTERCONNECTING THE OTHER ENDS OF SAID RODS IN SAID PLANE, A (FORCE-) FORCED GUIDING BEARING SOLID WITH SAID TANK WITH WHICH SAID ELEMENT COOPERATES, EACH GUIDING BEARING HAVING A GUIDING PATH FORMING A SLIDEWAY CONSTITUTED BY A RECTILINEAR ELONGATED RECESS FORMING A SUBSTANTIALLY HORIZONTAL STRAIGHT SLOT WITH PARALLEL OPPOSITE EDGES, THE LONGITUDINAL PLANE OF SYMMETRY OF SAID SLOT BEING IN SAID NORMAL RELATIVE VERTICAL PLANE, SAID GUIDING ELEMENT CONSTANTLY ENGAGING SAID SLIDEWAY WITH BILATERAL CONTACT WHILE MOVING IN SAID NORMAL RELATIVE VERTICAL PLANE.

May 6, 1975 J. H. ALLEAUME Re. 28,411 METHOD AND DEVICE FOR SUPPORTING ACONVEYED TANK AGAINST ROLL AND PITCH Original Filed Jan. 6, 1971 3Sheets-Shoat 1 P 2 N0 2 2 4 H W J y 1975 J. H. ALL'EAUME Re. 28,411

METHOD AND DEVICE FOR SUPPORTING A CONVEYED TANK AGAINST ROLL AND PITCH3 Shoots-Shoot 2 Original Filed Jan. 6, 1971 y 1975 J. H. ALLEAUME Re.28,411

METHOD AND DEVICE FOR SUPPORTING A CONVEYED TANK AGAINST ROLL AND PITCHOriginal Filed Jan. 6, 1971 3 Sheets-Shea; 3

JE W/ H.

United States Patent- Re. 28,411 Reiss-ued May 6, 1975 28,411 METHOD ANDDEVICE FOR SUPPORTING A CONVEYED TANK AGAINST ROLL AND PITCH Jean H.Alleaume, Saint Cloud, France, assignor to Technigaz, Paris, FranceOriginal No. 3,712,257, dated Jan. 23, 1973, Ser. No. 104,239, Jan. 6,1971. Application for reissue June 27, 1973, Ser. No. 374,036

Claims priority, application France, Apr. 30, 1970, 7016004 Int. Cl.1363b 25/08 U.S. Cl. 114-74 A 13 Claims Matter enclosed in heavybrackets appears in the original patent but forms no part of thisreissue specification; matter printed in italics indicates the additionsmade by reissue.

ABSTRACT OF THE DISCLOSURE A method of compensating by means of externalbearing reactions for the roll and pitch forces, a rigid shipborne tankmovably suspended at discrete external points distributed along theperiphery of the said tank and consisting in applying said bearingreactions, without creating any normal [effect] efiorts onto said tankat discrete points along the tank periphery located in a same horizontalplane so as to be horizontal relative to said ship by being eachparallel with the local plane tangent to the tank perpendicularly to thenormal passing through the point of application of the bearing reactionconsidered.

The present invention relates generally to and has essentially for itsobject a method of compensating for [or] balancing and absorbing, bymeans of external bearing reactions, the forces produced by roll and/orpitch motions on a rigid storage tank or container being conveyed by avehicle, as well as a supporting device for carrying out the saidmethod, and the various applications and uses resulting from the workingthereof and the systems, assemblies, structures, equipments and plantsprovided with such devices.

In patent application Ser. No. 834,337 filed on June 18, 1969 in theapplicants name, now U.S. Pat. No. 3,5 83,- 352, there is disclosed astorage tank or container in particular a spherical tank or container,supported vertically by being movably suspended from a transportationvehicle at spaced external discrete points distributed all over theperiphery of the tank for instance substantially in one and the samerelative horizontal plane. It may be for instance a spherical storagetank intended to contain liquefied gases at very low temperatures, suchas liquefied natural gases such as methane, and which is mounted in thehold of a cargo ship, vessel or boat. The said previous patentapplication provides for supporting devices against roll and pitch,distributed respectively along two large vertical orthogonal meridiancircles which are respectively parallel with the longitudinal axis andthe transverse axis of the vehicle or the ship or boat. This knownarrangement is disadvantageous in that it necessitates the provision, inthe vehicle frame or in the ships hold or hull, of special stationarylinking or tying structures solid with the ships bull or with the frameof the vehicle in general for securing supports against roll and pitch;such special structures are costly and complicated.

This invention has mainly for its purpose to avoid the said disadvantageby creating a method of neutralizing the forces resulting from roll andpitch, enabling the said forces to be transmitted to the level of atleast one and preferably two spaced horizontal planes, by means of thecorresponding bearing reactions comprised in each horizontal plane. Tothis end, the method according to the invention is characterized in thatit consists in applying the said bearing reactions, without creating anynormal force, to the said storage tank at spaced discrete pointsdistributed all over the periphery of the said tank, at least some ofwhich are located in one end and the same relative horizontal plane andin such a manner as to be at least approximately horizontal with respectto the said vehicle by being each substantially parallel with the localplane tangential [to] with the tank in perpendicular rela tionship tothe normal passing through the point of application of the bearingreaction considered.

According to another feature of the invention, and more particularly inthe case of a storage tank having at least one geometrical axis ofsymmetry or of revolution which is at least substantially vertical withrespect to the said vehicle, and having a relative horizontal orequatorial plane of symmetry, such as for instance a spherical orspheroidal storage tank suspended in particular substantially at thelevel of the said plane, the points of application of the said bearingreactions are distributed [into] in at least two sets locatedrespectively in at least two relative, substantially horizontal planesextending substantially in symmetrical relationship on either side ofthe said horizontal plane of symmetry of the said tank, the points ofapplication of one of said sets being for instance shifted in theperipheral direction with respect to those of the other said set.

Such an arrangement offers the advantage of considerably simplifying thestationary bearing structure serving to neutralize the roll and pitchforces to which the tank is subjected. Such improvements are thereforeadvantageous in that they allow more economic and easier constructionwhile at the same time being undoubtedly efiicient. By carefullyavoiding any force normal to the tank, it is possible to reduce thedimensions of its structure, thus possibly enabling a considerablereduction in weight to be obtained.

The invention also relates to a device, in particular an auxiliarydevice, for supporting a tank against roll and/or pitch, the said deviceserving to carry out the aforementioned method and being associated witha system of main supports for movable and substantially verticalsuspension. The said device is characterized in that it comprises atleast one system of spacedstationary hearing members distributed allover the periphery of the said tank by being located at leastapproximately in at least one and the same relative horizontal plane andeach of which is substantially rigid or practically not [undeformable]deformable at least in the horizontal direction perpendicular to thelocal normal of the tank, passing through the bearing member consideredby being so connected with the said tank that the latter is immobilizedlocally in the said direction, but is freely movable in at least therelative vertical, substantially normal or radial, plane passing throughthe said bearing member.

According to another feature of the invention, the said storage tank isconnected to each said bearing member by an associtaed forced-guidingbearing solid with the said tank and co-operating with the said bearingmember through bilateral sliding or rolling contact.

According to still another feature of the invention, each said guidingbearing comprises a guiding path forming a slide or the like,constituted by an elongated rectilinear recess forming a straight,substantially horizontal slit or slot, the mutually opposite edges orfaces of which are substantially parallel and rectilinear or flat[plane] wherein the said associated normal vertical local plane is thelongitudinal plane of symmetry whereas the associated stationary bearingmember comprises at least one guiding element in the form of either atleast one skid [skate] or at least one rotary roll or ball constantly[engaged in] engaging the said slide in sliding or rolling relationship[to] with said slide.

According to still another feature of the invention, there are providedat least two systems of said bearing members arranged for instance attwo levels located in particular symmetrically on either side of thehorizontal plane of symmetry of the tank, the said bearing members beingfor instance [shifted] mutually offset in the peripheral directionrespectively from one level to the other.

The invention will be better understood and other purposes, features,details and advantages thereof will appear more clearly from thefollowing explanatory description, with reference to the appendeddiagrammatic drawings given solely by way of example illustratingvarious forms of embodiment of the invention and wherein:

FIG. 1 is a cross-sectional view of a ship, vessel or boat conveying oneor several spherical tanks equipped with a device according to theinvention;

FIG. 2 is a fragmentary sectional view [to] at a larger scale, upon theline IIII of FIG. 1.

FIG. 3 is a fragmentary sectional view, partially broken away taken uponthe line IIIIII of FIG. 2;

FIG. 4 is a fragmentary sectional view taken upon the line IVIV of FIG.2;

FIG. 5 is a fragmentary top view [to] at a smaller scale, of a tankmounted in the ships hold with a said device according to one modifiedform of embodiment;

FIG. 6 is an enlarged fragmentary sectional view taken upon the lineVI-VI of FIG. 7 of a portion of the device illustrated in FIG. 5; and

FIG. 7 is a. fragmentary cross-sectional view, partially broken away,upon the line VIIVII of FIG. 6.

According to the example of embodiment illustrated in FIG. 1, theaforesaid transportation vehicle is constituted by a ship, vessel orboat, the double hull of which is indicated generally by the reference[digit] numeral 1, and comprises at its upper portion a main deck 2. Inthe hold 3 of the vessel are mounted one or several storage tanks orcontainers, for instance spherical tanks or containers 4 projecting forinstance above the main deck 2 with [by] their upper portion passingthrough the corresponding hold hatchway 5. Each tank 4 has preferablyits center 6 located in the medial longitudinal vertical plane 7 of thevessel. Each tank is for instance intended to contain liquefied gas at avery low temperature. In this case, the tank 4 as well as all of itssupport and suspension members with which it is connected areadvantageously made from a noble steel which is resistant to lowtemperatures, such as for instance stainless steel or an equivalentmetal, and the inner [wall] walls 8 of the hold 3 are advantageouslycovered on their exposed surface facing the tank, with a layer ofsuitable heat-insulating material.

Each tank is movably suspended from vertical suspension members 9 of thetype described and illustrated for instance in the above-mentionedpatent application. It is to be understood that the subject-matter ofthe present invention may be considered in combination with thesuspension devices disclosed in the said prior patent application. Eachsuspension device 9 is constituted by a kind of hinged parallelogramarranged substantially in the meridian vertical local plane normal tothe tank, i.e. passing through the vertical axis of revolution 7 of thelatter and is composed of two parallel vertical rods 10 [hinged] pivotedrespectively at their lower ends by means of two horizontal hinge pins11 to a yoke 12 solid with the tank 4 and by their upper ends by meansof two horizontal pins 13 to a yoke 14 which is itself hinged by ahorizontal pin 15 to a stationary bracket 16 solid with a box-shapedannular structure 17 surrounding horizontally the tank 4 and securedunder the main deck 2 i.e. [against] adjacent to the ceiling of the hold3. Each yoke 12, 14 is constituted by two parallel vertical plates. Thesupports 9 are distributed horizontally about the tank 4 in spacedrelationship [to] with one another and the lower yoke 12 is so securedto the tank 4 that the equatorial plane 18 of the tank passessubstantially through both horizontal pins 11 of each yoke 12. The upper[hinge] pivot pins 13 and 15 are located substantially in one and thesame horizontal plane and the [hinge] pivot pin 15 is located in thevertical plane tangential to the equatorial plane 18 of the tank 4 andperpendicular to the meridian vertical plane passing through the rods 10for each suspension support 9.

Advantageously, there are provided two systems for preventing roll andpitch effects, namely, an upper system 19 and a lower system 20 placedrespectively at two superposed levels which are symmetrical with respectto their horizontal plane of symmetry or equatorial plane 18 of thetank, the upper system 19 being preferably substantially at the level ofthe main deck 2 of the vessel. For the sake of simplification of thedrawing, only two vertical suspension supports 9, two bearing members ofthe lower system 20 and two bearing members of the upper system 19,placed respectively on either side of the medial longitudinal verticalplane of the vessel, are shown, whereas the said supports and membersare distributed horizontally about the tank 4 at their respectivedifferent levels.

Each system of bearing members 19, 20 is secured to a stationary annularstructure 21, 22, the lower structure 22 being located in the hold 3 andsolid with the hull 1 and surrounding horizontally the tank 4 in spacedrelationship to the latter. As shown more particularly in FIGS. 2, 3 and4, each of the bearing members 23 of each system 19, 20 comprises aguiding element 24 mounted to roll [rollingly] or [slidingly] slide inthe horizontal and preferably also in the vertical direction in aguiding bearing 25 extending in a direction which is substantiallyradial or normal to the tank 4. All the guiding bearings of one and thesame system of bearing members 19, or 20, i.e. those located at one andthe same level, are advantageously carried by a substantially horizontalring 26 solid with the tank 4 and surrounding the latter externally,each guiding bearing 25 being constituted for instance by a rectilinearrecess provided in the said ring and the mutually opposite longitudinaledges of which, forming a guiding slide, are advantageously reinforcedby members 27 considerably increasing the height of the guiding bearingsurface.

Each bearing member 23 is advantageously constituted by a bracketsupport of substantially triangular, for instance, isosceles,configuration composed in particular of two overhanging rods 28, 29,connected. respectively by one of their ends with the externalstationary structure 21 or 22 spaced from the tank 4 respectively attwo, at least horizontally spaced, points 30, 31 which are locatedrespectively on either side of the associated local normal verticalplane forming the meridian or radial plane passing through the guidingelement 24 and the guiding bearing 25. The rods 28, 29 converge towardsand meet one another in the plane so as to be interconnected by theguiding element 24 forming the overhanging free apex of the saidtriangle.

In each system 19, 20, the bearing members are preferably substantiallyadjacent to one another as shown in FIG. 2, and the mutually adjacentrods 28, 29 of two successive bearing members 23 are connected with thestationary structure 21, 22 at points 30, 31 close to or coinciding withone another, so that each system of bearing members 19, 20 forms astructure having, as it were, a latticed or triangulated configuration.Both rods 28, 29 of each bearing member 23 have for instance at leasttheir respective points 30, 31 of connection with the stationarystructure 21, 22 located at two respectively different, superposedlevels and the rods are advantageously substantially horizontal by being[shifted] spaced vertically with respect to one another, so as to belocated on either side of the horizontal plane, or of the ring 26,containing the associated guiding bearing 25. Two adjacent rods 28, 29of two successive bearing members 23 of one and the same system 19 or 20are for instance [shifted] spaced vertically with respect to one anotheras shown in particular in FIGS. 3 and 4.

The guiding elements 24 pertaining to one of the systems 19 or 20 ofbearing members 23 are preferably respectively [shifted] spaced in theperipheral direction with respect to the guiding elements of the othersystem, for instance, in such a manner that the guiding elements 24 ofone system are respectively arranged in the medial [mediating] meridianvertical planes between two successive guiding elements 24 of the othersystem. Each said guiding element 24 is advantageously constituted by asliding [skate] skid at least that [the] [portion] portions of whichengaging [engaged in] the associated guiding slide 25 [of which] has asubstantially prismatic lateral surface with a substantially verticalaxis and with for instance a square or rectangular cross-section, andthe height or vertical length of which is sufficient to ensure permanentguiding of any mutual relative vertical displacement of the said tankand/or the said guiding element 24.

Such relative mobility of the-tank 4 in vertical translatory motion[translation] with respect to the guiding elements 24 may be caused inparticular by the elongation [lengthening] of the suspension rods of thevertical supports 9 resulting from the increase in weight of the tankduring the filling thereof, whereas the relative mobility of the guidingelements 24 may result from a possible bending deformation of thebearing members or rods 23. Each rod 28, 29 of each said bearing member23 may be rigidly secured at its mutually opposite ends to[respectively] the associated guiding element 24 and to the saidstationary structure 21 or 22 respectively, for instance by Welding. Inthis case, each guiding [skate] skid 24 is advantageously constituted bya body in the form of a rectangular or a square parallelepiped which isset by its two adjacent longitudinal edges respectively inthe rods 28,29 by being welded to the latter. At their opposite ends, the rods 28,29 areeach secured to the stationary structure 21, 22 for instance bywelding through the medium of an interposed [shoe] pad or the like 32which is advantageously constituted by an angle-piece or the like.

Generally, each bearing member 23 is advantageously in the shape of aright-angled isosceles triangle, the rightangle apex of which isconstituted by its guiding element 24, so that the successive rods ofone and the same system of bearing members are respectivelyperpendicular to one another.

FIGS. 5, 6 and 7 illustrate a modified form of embodiment wherein eachsystem of bearing members 19', 20' is at a level at least close to thehorizontal plane of symmetry or equatorial plane 18 of the tank 4 andthe systems 19' and 20' are in fact arranged as close as possible to oneanother and have for instance their rings 26 carrying the guidingbearings arranged respectively above and below the [hinge] yokes forpivotal connec tion 12 for the vertical suspension rods 10 by beingplaced [against] adjacent to the said yokes which thus serve asdistance-pieces for the rings 26 as shown in FIG. 7. In this example,both rods 28, 29' of each bearing member 23' are [hingedly] pivotallymounted for instance substantially in coaxial relationship on theirassociated guiding element 24' which comprises to this end two aligned,mutually opposite pivot pins 33, i.e. an upper pivot pin and a lowerpivot pin which are substantially vertical and serve as hinge pins bybeing engaged in corresponding end eyes 34 at the ends of the rods 28'and 29. It is seen that both rods 28', 29 of each bearing member 23 arevertically [shifted] spaced with respect to one another, so that their'ends 34 [hinged] pivoted on the common guiding element 24 aresuperposed. The portion of the guiding element 24' which is locatedbetween two pivot pins 33 [are] is preferably :in the shape of a squareor rectangular parallelepiped [shaped] slidingly mounted in the guidingbearing 25. Both adjacent rods 29', 28a or 29b, 28' of two successivebearing members 23 of one and the same system 19' or 20 are [hingedly]pivotally connected with the stationary structure 21', 22 by having forinstance their adjacent ends in mutual superposition about one and thesame vertical [hinge] pivot pin 35 mounted in a common yoke solid withthe said stationary structure. As

already indicated previously, if the tank 4 is to contain for instanceliquefied gases at very low temperatures, the tank and all its bearingmembers 19, 29 or 19, 20' and all its suspension members 9 are made froma metal capable of withstanding low temperatures, whereas heatinsulatingmeans are interposed in the connections of the said members with thestationary structures 21, 22 or 21, 22' supporting them. In the exampleconsidered, the stationary structure yokes 21', 22' supporting the pivot[hinge] pins 35 and the corresponding ends of the rods 28', 29 are madefor instance from ordinary structural steel, whereas all the other[pieces] parts or portions shown in particular in FIG. 7 are made fromnoble steel, for instance from stainless steel, and heat-insulation withrespect to the stationary strucure 1, 21, 22' is [ensured] provided bysleeves 36 made from heat-insulating material and supported by the yokesof the stationary structures 21', 22 and in which sleeves are mountedthe [hinge] pivot pins 35.

As the systems of bearing members 19 20 are near to the equatorial plane18 of the tank 4, it is necessary to provide for a greater spacingbetween the guiding bearings 25 and the tank 4 in order to avoid anyinterference, in particular with the rods 10 of the vertical suspensionsupports 9. It should be noted in this connection that the first form ofembodiment illustrated respectively in FIGS. 1 to 4-, is moreadvantageous, to a certain extent, than the second form of embodimentillustratedin FIGS. 5 to 7. Indeed, in the first form of embodiment thestresses are less concentrated in proximity to the equatorial plane thanin the second form of embodiment in which they combine with the stressesresulting from the vertical suspension. On the other hand, a betterbalancing of the respectively upper and lower tank halves or hemispheresis obtained in the first form of embodiment owing to the greatervertical spacing of the system of bearing members 19, 20. Lastly, in thefirst form. of embodiment, since the systems of bearing members 19,. 20are located outside of the region of where the vertical suspensionsupports 9 are arranged,

the points of application of the bearing reactions through the medium ofthe co-operation of the guiding elements 24 and the guiding bearings 25are closer to the wall of the tank 4, thus resulting in a reduction ofundesired residual torques in the wall of the tank as compared with thesecond form of embodiment.

It is seen that in the second form of embodiment, the bearing members ofthe lower system 20 are [shifted] ofiset in the peripheral directionwith respect to the bearing members of the upper system 19 in the samemanner as in the first form of embodiment. The [hinge] pivot pins 11 ofthe vertical suspension rods 10 are located substantially in theequatorial plane of the tank 4. Irrespective of the said shift in theperipheral direction, the two superposed system of bearing members 19,20 or 19', 20' are preferably substantially identical in both forms ofembodiment and the Vertical pins of the guiding elements of both systemsare advantageously located substantially on one and the same cylindricalsurface concentric with the axis of revolution 7 of the spherical tank4.

In FIGS. 6 and 7 it is observed that in this form of embodiment therings 26 carrying the bearings are radially Wider than in the precedingform of embodiment, so that it is necessary to provide in the upper ring26 openings 40 enabling the suspension rods 10 closest to the tank to befreely passed therethrough, whereas the suspenat least one transversepartition forming a cofferdam 41 and on the other hand by the wall ofthe double hull 1 of the ship, vessel or 'boat comprising an innerplanking 37 and an outer planking 38 defining therebetween anintermediate space 39 forming for instance a lateral [ballastingcontainer] ballast tank.

Of course, the invention is by no means limited to the forms ofembodiment described and illustrated which have been given by way ofexample only. In particular, it comprises all the means constitutingtechnical equivalents to the means described as well as theircombinations, should the latter be carried out according to the [spirit]gist of the invention.

What is claimed is:

1. An auxiliary device for supporting a tank against roll and pitch andassociated with a system of main movable and substantially verticalsuspension supports, said device comprising at least one set ofstationary bearing members substantially adjacent to one another anddistributed along the periphery of said tank at least approximately inone and the same relative horizontal plane, each bearing membercomprising a substantially triangu lar bracket support comprising inparticular two overhanging rods, a stationary external structure spacedfrom said tank, [respectively at two, at least horizontally spacedpoints of the tank located respectively on either side of the normalrelative vertaical plane passing through said member], one of the endsof said rods being connected to said structure, said rods projectingrespectively from two at least horizontally spaced points of saidstructure located respectively on either side of the normal relativevertical plane passing through said member and said rods convergingtowards said plane, a guiding element interconnecting the other ends ofsaid rods in said plane, a [force-] forced guiding bearing solid withsaid tank with which said element cooperates, each guiding bearinghaving a guiding path forming a slideway constituted by a rectilinearelongated recess forming a substantially horizontal straight lot withparallel opposite edges, the longitudinal plane of symmetry of said slotbeing in said normal relative vertical plane, said guiding elementconstantly engaging said slideway with bilateral contact while moving insaid normal relative vertical plane.

2. A device according to claim 1, wherein the bearing members located atone and the same level are substantially adjacent to one another and theadjacent rods of two successive bearing members are connected with saidstationary structure at two at least adjacent points.

3. A device according to claim 1, wherein each guiding element isconstituted by a sliding. block-forming pad at least that portion ofwhich engages said slideway has a substantially prismatic lateralsurface, the axis of which is substantially vertical and thecross-section of which is rectangular and the vertical length of whichis sufficient to constantly ensure the guiding of any mutual relativevertical displacement of said guiding element.

4. A device according to claim 1, wherein both of said rods of eachbearing member have at least their respective points of connection withsaid stationary structure located at two respectively different levelsand are substantially horizontal and [shifted] spaced vertically, so asto be located on either side of the horizontal plane containing theassociated guiding bearing.

5. A device according to claim 4, wherein said two rods of each bearingmember are [hingedly] pivotally connected in substantially coaxialrelationship, with the associated guiding element, comprising to thisend two mutually opposed pivot pins which are aligned and substantiallyvertical and serve as hinge pins, each of said rods being [hingedly]pivotally connected also with said stationary structure aboutrespective, substantially vertical [hinge] pivot pins.

6. A device according to claim 4, wherein two adjacent rods of twosuccessive bearing members of one and the same system are ofisetvertically with respect to one .annther.

7. A device according to claim 6, wherein two adjacent rods of twosuccessive bearing members of one and the same system are [hingedly]pivotally connected with said stationary structure in mutualsuperposition about one and the same vertical [hinge] pivot pin mountedin a common clevis.

8. A device according to claim 6, wherein each rod of each said bearingmembers is rigidly secured [by] with its opposite ends [respectively] tothe associated guiding element and to said stationary structure.

9. A device according to claim 1, wherein at least two sets of saidbearing members are arranged at two levels located symmetrically oneither side of an horizontal plane of symmetry of said tank, saidbearing members being respectively shifted in the peripheral directionfrom one level to the other.

10. A device according to claim 9 [characterized in that] wherein saidguiding bearings of one and the same system of bearing members locatedat one and the same level are carried by a substantially horizontal ringsolid with said tank and surrounding the latter externally, each guidingbearing being constituted by a recess provided in said ring.

11. A device according to claim 9, wherein said tank and all of itsbeating and suspension members are made from a metal capable ofwithstanding low temperatures [whereas] and including heat-insulatingmeans interposed in the connections of said members with the stationarystructures supporting them.

12. A device according to claim 9, for a tank mounted in the hold of acargo ship having a main deck wherein said two sets of bearing memberscomprise an upper set and a lower set placed respectively at twosuperposed levels, symmetrical with respect to the said horizontal planeof symmetry of the said tank, the upper set being substantially at thelevel of said main deck of said ship.

13. An auxiliary device for constraining a tank against roll and pitchand associated with a system of essentially weight-bearing substantiallyvertical supports, said device comprising at least one set of keyingmeans distributed about the periphery of said tank at leastapproximately on a same horizontal level, each keying means being atleast approximately symmetrical with respect to a vertical centre planelocally normal to the wall surface of said tank, and comprising: astationary structure arranged outside ,of and spaced from said tank; akey member carried by said structure and projecting therefromsubstantially horizontally towards said tank; key-way defining meansintegral with and projecting outwards from said tank and co-operatingwith said key member in forced guiding relationship, said key memberincluding a terminal slideblock portion formed with substantially flat,vertical, opposite, side faces located on either side of said verticalplane of symmetry, said key-way defining means being formed with anelongated, substantially straight slot forming a verticalthrough-passageway and extending outwards from a closed end thereof nearsaid tank to its opposite open end remote from said tank, said slotbeing open at its top and bottom and having opposite edges formingvertical side wall portions located on either side of said plane ofsymmetry, said slot being constantly engaged in sliding relationship bysaid slide-block portion and reciprocally movable through thermalexpansion and contraction of said tank horizontally inwards and outwardsvertically upwards and downwards in either direction relative to saidslide-block portion with two degrees of freedam of motion insubstantially parallel relation to said vertical local plane ofsymmetry.

References Cited The following references, cited by the Examiner, are ofrecord in the patented file of this patent or the or-ginal patent.

i (References on following P 9 UNITED STATES PATENTS Bridges 11474 ALeathard 114-74 A Bridges 11474 A Cliflord 22015 Collins 22015 Morrison114-74 A 10 2,926,810 3/1960 Yeager 22015 3,251,501 5/1966 Mesnager220-15 3,583,352 6/1971 Alleaurne 114-75 A S. M. GOLDSTEIN, AssistantExaminer

